Upload
electrico-ingenieria
View
213
Download
0
Embed Size (px)
Citation preview
7/28/2019 Smart Distribution Network.pdf
1/5
2011The International Conference on Advanced Power System Automation and Protection
APAP2011 www.apap2011.org
*Corresponding author (email: [email protected])
Research on technical framework of smart distribution networkLI JianFang, MENG XiaoLi, SONG XiaoHui
China Electric Power Research Institute, Beijing 100192, China
Abstract: The future development trend of electric power grid is smart grid, which include such features as flexible, clean, se-
cure, economic, and friendly and so on. Smart grid involves power generation, transmission, transformation, distribution, con-
sumption and dispatching. Distribution network locates at the end of power system, and due to its direct connection with con-
sumers, the quality and ability of power supply is guaranteed by it. In this paper, the connotation, characteristics and the de-
velopment goals of smart distribution network in China are expounded firstly. Secondlythe technical framework of smart
distribution network, which include network infrastructure, information communication system and intelligent application sys-
tem, is put forward. The main technical compositions of the framework are briefly discussed in succession. Lastly, the sugges-tion on development path of smart distribution network in china is proposed, in the hope of providing reference to the further
research and implementation of smart distribution network.
Keywords: smart distribution network, technical framework, information and communication system, intelligent ap-
plication, development path
1 Introduction
With the increasing global pressure on resource and envi-
ronment, social improving the requirement for environment
protection, energy conservation and emission reduction,
sustainable development day by day. Meanwhile, theprocess of power market is promoting and the requirement
of the consumers for power supply reliability and power
quality is increasing, the power industry is facing unprece-
dented challenges. To provide more safe, reliable, clean and
efficient power supply become the common goal of the
power industry. In the future, the power grid will produce
more data and information, support bidirectional flow of
load and information, adapt to the access of various kinds of
distributed energy resource, meet the demands of consumers,
and the efficiency and social economic benefits of grid as-
sets is improved significantly. The United States and some
European Union countries put forward the concept of smart
grid, and consider it the future development trend of electric
power grid [1-4].
Due to the different development environment and driving
factors, there are differences in development path and empha-
sis among different countries. Based upon national conditions,
every country gives its own definition of smart grid. The core
of the smart grid is to conserve energy, reduce emission, im-
prove efficiency and reliability. Smart grid has become a vi-
sion for power industry all over the world, and it will promote
changes and improvements of the power industry.
Smart grid involves power generation, transmission, trans-
formation, distribution, consumption and dispatching [5-6].
Distribution network locates at the end of power system, and
due to its direct connection with consumers, the quality and
ability of power supply is guaranteed by it. Therefore, the
construction of smart distribution network plays an important
role of the smart grid.
2 The connotation and characteristics of smart
distribution network
2.1 The connotation of smart distribution network
Compared with distribution automation (DA), smart distri-
bution network covers all the content of distribution auto-
mation and even more, it nearly covers all the technology in
primary side and secondary side. Smart distribution network
is enhanced in performance, adapt to the access of
large-scale distributed energy resource and interacting with
consumers.
Smart distribution network covers a wide range, and thereis no generally accepted definition of smart distribution net-
work so far.
The core components, necessary systems and equipments
in smart distribution network are introduced in paper[7]. The
goal of the smart distribution network is to extend equipment
life, determine the priority of grid asset replacement, reduce
the cost of network reconstruction and avoid fault in advance
and so on [8]. It is noted that the smart distribution network is
the extension of advanced distribution automation (ADA), and
the main differences between traditional distribution network
and smart distribution network are: adapt to the access of var-
ious kinds of distributed energy resource and micro-grid oper-ation, encourage interaction with consumers [9].
___________________________________
978-1-4244-9621-1/11/$26.00 2011 IEEE
7/28/2019 Smart Distribution Network.pdf
2/5
2011The International Conference on Advanced Power System Automation and Protection
At present, many countries have formed a consensus during
the construction of smart distribution network based upon
national conditions. The connotation of smart distribution
network can be summarized as such aspects: based on physi-
cal entity grid, includes various kinds of distribution facilities
such as switches, distribution terminals, sensors; integrates avariety of modern advanced technology such as sensor mea-
surement, automation technology, communication technology,
information technology, control technology; adapt to the
access of various forms of distributed energy resource, energy
storage device and electric vehicle. Compared with traditional
distribution network, smart distribution network is more flexi-
ble and adjustable, significantly improves the security, relia-
bility, quality of power supply and the social economic bene-
fits of energy resource.
2.2 The characteristics of smart distribution network
Smart distribution network performances well in power
supply security, power quality and efficiency of grid assets.The characteristics of smart distribution network can be
summarized as: informationization, automation and interac-
tion(abbreviated as Three-tions).
Informationization is the basis for the realization of smart
distribution network. Informationization means the ability of
highly integrated, multi-share, deeply excavation of the
real-time and non real-time information, and it can be classi-
fied into two categories: the informationization of power pro-
duction and control, the informationization of power man-
agement.
Automation is the visual representation of the development
level of the smart distribution network, not limited to distribu-tion automation, but include optimization of network control
strategy, monitor of operation and fault restoration.
Interaction is the inherent requirement of smart distribution
network. Interaction has two meanings: firstly, adapt to the
access of various forms of distributed energy resource; se-
condly, interact with consumers, consumers can choose the
time of power consumption based on real-time price and have
own distributed energy resource interacted with the power
system[10-14].
2.3 The development goals of smart distribution network in
ChinaGeneration, transmission, transformation, distribution, con-
sumption and dispatching are the six application areas of
strong smart grid. The development goals of the smart dis-
tribution network in China are: a strong frame structure with
the characteristics of efficient and flexible, have a good
performance in reconfiguration, power flow optimization
and acceptance of distributed energy, compatibility and uni-
fied control of the distributed energy resource and energy
storage device, high reliability and quality of power supply.
3 The technical framework of smart distribu-
tion network
The construction of smart distribution network in China
needs to start with the basic areas and make the technical
framework in line with the development in China clear.
Smart distribution network, which combine modern ad-
vanced technology with traditional distribution technology and
focus on the improving of the overall performance and saving
of the overall cost, makes revolutionary changes in network
structure, relay protection and operation control mode and so
on.
The technical framework, which covers planning, construc-
tion, operation and management of the distribution network,
can be divided into physical entity layer, data layer and appli-
cation layer logically. The framework includes network infra-
structure, information communication system and intelligent
application system, just as figure 1 show.
7/28/2019 Smart Distribution Network.pdf
3/5
2011The International Conference on Advanced Power System Automation and Protection
Figure 1 The technical framework of smart distribution network.
As the physical basis of the smart distribution network, the
physical entity layer locates at the bottom of the framework;
the data layer is the tremendous database of smart distribu-
tion network and it can provide data for the application
layer; the intelligence of distribution network is well embo-
died in the application layer.
3.1 Strengthen the network infrastructure
A strong and flexible network and intelligent distribution
equipments of safety and reliability are the basis of smart
distribution network.
(1) Strong and flexible network. Strong network is the pri-
mary goal of the smart distribution network construction in
China. Grid-connection of various kinds of distributed energy
has a great impact on network planning. The ability againstnatural disasters and other emergencies is necessary in future.
Innovation in planning process, planning modeling and plan-
ning method is indispensable.
(2)Intelligent distribution equipments. Intelligent distribu-
tion equipments include monitoring devices, protection devic-
es, control devices in secondary side and static compensators,
solid-state switches, distributed generation and energy storage
devices in primary side.
3.2 Construction of information and communication system
It is necessary to acquire various kinds of meter data, which
with the characteristics such as large amount, plenty of the
information points, higher requirement of real-time. The
requirements above-mentioned cant be satisfied in tradi-
tional information communication system, therefore ad-
vanced sensing technology, unified information model and
open communication platform should be enhanced.
(1)Advanced sensing technology. Based on sensing tech-
nology, power system planners and operators can acquire a lot
of data such as load, voltage, current, power factor, phase rela-
tion, temperature, and monitor the healthy state of equipment,
recognize the operation condition, evaluate the security and
stability of power system.
(2)Open communication platform. Existing communication
system, which based on the one-way flow of information,
cant meet the requirement of bi-direction flow in smart dis-
tribution network. A high-speed, bi-direction, real-time andintegrated communication system is needed. The construction
of communication system needs to focus on the following:
open communication architecture, in order to form a plug and
play environment; unified technique standards, in order to
achieve seamless communication among equipments and sys-
tems.
(3)Unified information platform. The problems of existing
information systems are as follows: lack of unity of data
source, lack of data maintenance in time and lack of coordina-
tion. A unified information platform with the characteristics of
a wide-range of information source, support bi-direction in-
formation flow and data sharing should be developed.
7/28/2019 Smart Distribution Network.pdf
4/5
2011The International Conference on Advanced Power System Automation and Protection
3.3 Develop intelligent application
At present the data application of network in China is
still in the basic level. Intelligent application should be en-
hanced in order to meet the requirements of smart distribu-
tion network.
(1)Fast simulation and modeling. The achievement of fastsimulation and modeling is to offer decision-making support
for relay protection, network reconfiguration, fault isolation
and restoration by means of state estimation, power flow cal-
culation, load forecasting, security evaluation and predictive
contingency analysis.
(2)Operation optimization. To minimize the line loss under
normal condition, optimize operation mode under overhaul
condition and realize fast restoration under fault condition in
order to keep the distribution network operate in security and
economy.
(3)Intelligent dispatch. With the development of advanced
sensing technology, wide-area measurement system (WAMS)and advanced metering infrastructure (AMI), observability of
network is strengthened. Its probable to achieve real-time
state estimation and precise control of the whole network.
Dispatch in smart distribution network is more complicate and
difficult due to the grid-connection of distributed energy and
the bi-direction flow of energy.
(4)Intelligent control. Deep interaction between consumers
and power system make intelligent control a multi-objective
problem. Besides security, reliability and economy, which are
considered in traditional network, energy conservation and
emission reduction as well as improvement of efficiency
should be taken account of.(5)Grid-connection of distributed energy resource. After the
distributed energy resource connected to the traditional distri-
bution network, the configuration of relay protection and
safety automatic devices become more complicate and should
be reset to satisfy the bi-direction flow of load and information.
The power output of distributed energy changes now and
again, with the characteristics of fluctuation and intermittence,
and is prone to bring shock to power system.
Besides network infrastructure, intelligent distribution
equipments, communication technology and information
technology as mentioned above, standard systems are also
indispensable[15]. Based on the unified standard, information
interaction, communication and resource sharing among
equipments and systems become more convenient.
4 Development path of smart distribution net-
work
The development path of smart distribution network in
China should be based on the development status and com-
bined with the development concept in China as well as
oversea experience.
(1)Strengthen the construction and optimization planning of
distribution network to form a strong and flexible physical
entity network of sufficient power supply capability and high
reliability.
(2)Upgrade distribution automation and self-healing control
in order to keep power system operate in security, reliability,
economy and efficiency.
(3)Construction of information and communication system.Besides electric power technology, smart distribution network
needs information and communication system with the cha-
racteristics of high-capacity, high-speed, real-time and ex-
tensibility as supporting platform.
(4)Strengthen the interaction with consumers. It is neces-
sary to develop further research on grid-connection of distri-
buted energy, energy storage technology and charging man-
agement of electric vehicle in order to provide solution for
consumers.
(5)Development of exploratory research. Smart grid means
important technological innovation; we should make every
effort to exploratory research.Smart distribution network is a systemic project and needs
a wide range of support: policy support and financial support
of the government in order to provide a good external envi-
ronment, combination research of research institutes, power
industry and equipment manufacturer.
5 Conclusion
The construction of smart distribution network in China will
be a long and arduous process. Further research on network
infrastructure, information and communication system, in-
telligent application and unified standard system are neces-
sary.
Smart distribution network needs support of government
and cooperation of research institute, power industry and
equipment manufacturer.
Along with the development and the further research of the
smart distribution network, the technical framework and its
development path will become more clear.
This work was supported by the Science and Technology Projects of StateGrid Corporation of China (Grant No. ND71-10-005, No. ND71-11-002).
1 Zhang Wenliang, Liu Zhuangzhi, Wang Mingjun, Yang Xusheng.
Research status and development trend of smart grid. Power System
Technology, 2009, 33(13): 1-11.
2 Hu Xuhao. Smart GridA development trend of future power grid.
Power System Technology, 2009, 33(4): 1-5.
3 Wang Xiuli. Brief discussion on the smart grid. Water Resources and
Electric Power, 2009, 35(4): 13-20.
4 Han Feng, Yin Ming, Li Jun, Zhang Yibin, Sun Qiang. Discussions on
related issues of smart grid development in China, 2009, 33(5): 47-53.
5 Wang Zhidong, Li Hui, Li Jun, Han Feng. Assessment index system
for smart grid. Power System Technology, 2009, 33(17): 14-18.
6 Zhong Jin, Zheng Ruimin, Yang Weihong, Wu Fuli. Construction of
smart grid at information age. Power System Technology, 2009, 33(13):
12-18.
7 Yu Yixin. Intelli-D-Grid for the 21st century. Southern Power System
Technology Research, 2006, 2(6): 14-16.
7/28/2019 Smart Distribution Network.pdf
5/5
2011The International Conference on Advanced Power System Automation and Protection
8 Zhang Tiefeng, Wang Jiangtao, Yuan Jinsha. Research of intelligent
distribution network. Telecommunications for Electric Power System,
2007, 28(181): 49-52.
9 Ma Qiyan, Qin Lijun. Key technologies of smart distribution grid.
Modern Electric Power, 2010, 27(2): 39-44.
10 Liu Wei, Peng Dong, Bu Guangquan, Su Jian. A survey on system
problems in smart distribution network with grid-connected photo-
voltaic generation. Power System Technology, 2009, 33(19): 1-6.11 Wang Mingjun. Some highlights in relation to smart grid. Power
System Technology, 2009, 33(18): 9-16.
12 Chen Shuyong, Song Shufang, Li Lanxin, Shen Jie. Survey on smart
grid technology. Power System Technology, 2009, 33(8): 1-7.
13 He Guangyu, Sun Yingyun. Smart grid foundation[M]. Beijing: Chi-
na Electric Power Press, 2010.
14 Wang Chenshan, Li Peng. Development and challenges of distributed
generation,the micro-grid and smart distribution system. Automation
of Electric Poewr Systems, 2010, 34(2): 10-14, 23.
15 Lin Yufeng, Zhong Jin, Wu Fuli. Discussion on smart grid supporting
technologies. Power System Technology, 2009, 33(12): 8-14